Freshwater crabs in Singapore

Whilst Singapore is a built up modern metropolis, there are still many areas in which fascinating fauna can be found, some endemic, some widespread. Birdwatching has always been my first love but in the last year, I have also taken to the macro world and herpetology (see my previous blog posts).

With my local nature expert J, we recently started seeking out some of Singapore’s 6 known species of freshwater crabs, three of them endemic, all locally vulnerable or critically endangered. The endemic ones are the Singapore freshwater crab johora singaporensis, Johnson’s freshwater crab and the swamp forest crab. The other three non-endemic species are the lowland freshwater crab, peraccas land crab and little land crab…

So going to where we thought we’d have success, we found the first of the non-endemic species…A Peracca’s land crab which was a way away from water…at first I thought surprisingly so…but on reflection, I guess it is called a ‘land’ crab for a reason! It was the most beautiful of the three crabs that I shall be describing in this post…the front part of the head and carapace leading into the claws were just brilliantly orange red…searching the literature (and much of the research work was of course done by Prof Peter Ng from the National University of SIngapore), it is apparently difficult to distinguish the Peracca from the Little Land Crab.

Peracca’s land crab

dorsal rear view

another view

Peracca’s land crab up close

another up close view..

this shot taken with my Leica 75mm with macro adaptor/raynox: v hard to focus but still fun

And on this visit we also saw…

scorpion

caterpillar..

Returning a few weeks later to the same spot, J soon found what we had really wanted to find, the critically endangered Singapore Freshwater Crab, Johora singaporensis. Barely more than an inch across, it was hardly as impressive as the Peracca’s. J is an incredible resource of knowledge on all things nature related and educated me on the features that confirmed that this was indeed Johora singaporensis. The first thing he said was that it’s purple hued….purple??? It just looked a dirty grey at first sight but with a light on it, the shell glowed a subtle purple….he also pointed out the hairy shell and legs, and the yellow pointed tips of the pincers

Johora singaporensis note the purplish hue, hairs on the carapace and the larged yellow tipped pincers

it looks darker from this angle

up close with the Singapore Freshwater Crab

And finally, we also found this crab…a dirty greenish brown fellow…half the size of the previous one….still very attractive